Tfie American Toad, Bufo lentiginosus americanus LeConte. 29 



breeding temperature may cause them to become inactive, remain 

 beneath the surface of the water, and delay ovulation. In one case I 

 have circumstantial evidence to show a delay of 6 days. 



The male embraces the female by digging its forearms into the axilla 

 of the female, the forefingers of the male being folded up (Plate n, 

 Fig. 1). In this way it is clearly seen how the dorsal horny excres- 

 cences of the first three fingers of the male come into use. 



Sometimes the males resume the embrace after the females have laid 

 their complements. The longest record is an embrace for 12 days after 

 ovulation. In three instances, where pairs laid in water or in dry jars, 

 the males resumed embraces soon after the completion of ovulation. 

 Each had a lumbar amplexation or one midway between lumbar and 

 axillary. They so remained for 6 days, and part of the time throughout 

 this period they were in the lumbar amplexation. Only once (April 1, 

 1910) has a lumbar embrace been recorded in the field. 



That cross-embraces are possible with this species, every naturalist 

 knows. Cross-embraces between males of the genus Bufo and females 

 of Rana pipiens, palustris, and clamaia were noted. In one instance, 

 March 31, 1910, a male Bufo seized a female Rana pipiens and held her 

 with right arm in front of and the left arm behind the forearms of the 

 female frog. The arms of the male toad almost met on the breast 

 and there was no suggestion of the axillary or supra-axillary form of 

 embrace. A little later, both forearms were placed behind the forearms 

 of the frog, but they met on the breast, as in the fashion of the male 

 Rana. In another case, a curious embrace was secured April 8, 1908, 

 with a male Bufo and a female Rana clamaia. The toad had his right 

 hand dug into the axil Bufo fashion, but the left arm and hand went 

 around on the breast Rana fashion. After a period it lost its grasp and 

 regained a lumbar embrace, which it maintained only long enough to 

 enable it to work slowly up to the customary axillary hold. 



Furthermore, Bufo is the North American Anuran most easily led into 

 abnormal embrace with dead animals, inanimate things, or live animals 

 of other orders or classes; for example, on April 28, 1911, in the labora- 

 tory, a male toad was embracing a dead female Rana pipiens (Plate iv, 

 Fig. 1) . In the field, males have been found holding dead females. And 

 almost every naturalist has tried out the amorous frenzy of the males 

 with a finger, with sticks, stones, or a dozen other objects. 



OVULATION. 



At the spawning season, to find a thousand toads in one small pond 

 is not a rare observation ; hundreds of pairs may be recorded laying at 

 one time; and in one instance 10 pairs were secured within an area 

 H feet square. Any water-hole, ditch, or transient pool may have 

 one or more toads at this season. They prefer the shallows (Plate xn, 

 Fig. 1) and are not particular whether it be grassy, weed} 7 , or swampy, 



